#define _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
int main()
{
	int a = 0;
	int b = 0;
	scanf("%d %d", &a,&b);
	while (b != 0)
	{
		int temp = b;
		b = a % b;
		a = temp;
	}
	printf("%d", a);

}